The tribes who inhabited Uruguay were the fiercest Indians encountered by the conquerors of South America. For two centuries they succeeded in preventing the establishment of settlements in their territory and kept out Spanish intruders at the point of the sword. The Spaniards greatly coveted the north bank of the Plate and made effort after effort to get a foothold there, but these savages managed to maintain themselves for a hundred and fifty years in the very face of Buenos Aires. The river shore itself was the last accessible and fertile region to be subjected to the whites. A century elapsed after the foundation of Buenos Aires before Colonia was occupied by the Portuguese, and another fifty years went by before Montevideo had been settled and fortified. Uruguay in pre-Spanish times, as well as since, was a meeting-ground for different peoples. One after another the Guarany tribes crowded into this favoured region from the north and west, and the old inhabitants had to fight and conquer, or be thrust into the sea. The bravest, best armed, and best organised tribes survived in the harsh struggle. Of the Indians inhabiting Uruguay when the Spaniards discovered the Plate, the principal ones were the Charruas. They occupied a zone extending around from the Atlantic, along the Plate, and a short distance up the Uruguay. This strong and valiant race never submitted to the Spaniards, and when at last they were defeated and crowded back from the coast well on in the eighteenth century, they retired to the north and maintained their freedom for many years. They belonged to the great family of Tupi-Guaranies, who occupied most of eastern South America at the white man's advent, but they were more nomadic in their habits and had developed the art of war to greater perfection than the mother tribes of the more tropical parts of South America.